What is a cordel?

A strand is simply each individual "wire" of copper in a conductor. These come in different thicknesses and numbers, all depending on the type of cable and wire you have. The picture below shows an electric cable with 3 conductors/wires of 2.5 mm² (abbreviated as 3G2.5mm²) and has a single-stranded cord.

Single-stranded (one piece of cord), multi-stranded (many cords) and multi-stranded (most cords) say something about the thickness and quantity of the copper cords in the wire. These have different properties and are suitable for different things. The difference between single-wire, multi-wire and multi-wire is about the structure of the conductors in a cable:

Single-wire cable: Consists of a single solid conductor. It is stiff and provides good conductivity, but is less flexible, which makes it less suitable for applications where the cable must be bent or moved frequently.

Multi-core cable: Consists of several thin conductors (wires) that are intertwined or twisted together. This type of cable is more flexible than single-core cable and is therefore better suited for applications with a lot of movement.

Stranded cable: Similar to multi-stranded cable, but with the stranded wire having even more and thinner conductors. It provides maximum flexibility and is usually used in applications where the cable must be bent strongly or moved frequently.

Generally speaking, the more strands there are, the more flexible the cable will be, but this can also affect conductivity. The choice of cable type depends on the use and the requirements for flexibility and conductivity.